Method and Apparatus for Cleaning Delicate Textiles

ABSTRACT

The invention concerns an apparatus for cleaning delicate textiles, comprising a motorized and rotating drum housed in a fluid tight basket, at least a water inlet and a fluid outlet, at least a first container for a first chemical composition, and a heating means. According to the invention, the first container is appropriate to contain a warm mixture of water and the said first chemical composition, the apparatus comprises at least a conduit cooperating with a circulating means for mixing and circulating the said warm mixture between said first container and said circulating means, a means for injecting or spraying said mixture into said drum and over dry textiles, said circulating means having an inlet for said warm mixture and at least an outlet cooperating with at least a first end of a conduit opening at its second end into the drum. The invention further relates to a method implemented by such an apparatus.

BACKGROUND AND AREA OF THE ART

The invention relates to cleaning or wet cleaning (water based) of delicate textiles or other items. In the meaning of the present invention the term “delicate textiles” refers to items which have a tendency to lose dye or color, crease, felt or shrink when cleaned or washed in water. In order to avoid damages many of the delicate textiles are conventionally dry cleaned.

DESCRIPTION OF THE PRIOR ART

Two main types of textile cleaning are known: dry cleaning that relates to methods and apparatuses using non aqueous solvents; and wet cleaning using water as main component of the cleaning. In other words, dry cleaning relates to methods and systems that use non aqueous solvents whereas wet cleaning uses water as solvent.

Dry cleaning is thus based on the use of chemical compositions as solvents, most commonly perchloroethylene which has been identified as a hazardous air and ground water pollutant (listed as such under the Clean Air Act by the U.S. Environmental Protection Agency and declared as a toxic chemical by California in 1991); it has been also been associated with nervous-system disorders, severe skin irritation, liver and kidney disorders amongst industrial workers and listed as probable carcinogen by the International Agency for Research on Cancer (IARC). The use of perchloroethylene has been banned in California where it will be progressively phased out by 2023. As a consequence of the hazardous nature of perchloroethylene, processes utilizing it must be done at professional dry cleaning establishments using specialized dry cleaning equipment.

In recent years, the industry has responded with less toxic alternatives to perchloroethylene-based cleaning, including cleaning systems based on hydrocarbons, glycol ethers or cyclic siloxane. While these alternatives may have lower toxicity levels than perchloroethylene-based cleaning, they are still comparatively more toxic and have lower cleaning power than water-based cleaning. They are thus preferably avoided.

While non-aqueous solvent-based cleaning systems may be effective for removing oily soils and oily stains, they are not optimal for removing particulates such as clay soils or the more common water-soluble stains such as sugars, starch, protein etc. They also require special pre-treatment, mostly done manually, (pre-spotting), to remove stains.

Moreover, equipment for dry cleaning as well as other non-aqueous solvent based cleaning is typically more capital intensive than for wet cleaning. It also compares unfavourably with regard to operating costs and specifically with regard to repair and maintenance costs due to the greater technical complexity and higher energy and water consumption. In addition, as opposed to dry cleaning, there is no need for special removal of (hazardous) solvent sludge and used filters in wet cleaning.

Wet cleaning is a comparatively non-toxic, environmentally safe alternative to dry cleaning. It uses water as solvent as well as biodegradable soaps/detergents, conditioners and other compositions. The process of wet cleaning in a professional wet cleaning operation is similar to washing garments in a modern household washing machine, albeit in a controlled environment with regard to drum rpm (revolution per mn), temperature and water volume. However, professional wet cleaning operations require specially designed wet cleaning machines and dryers able to process high volumes and a greater variety of textiles.

Even if the quality of wet cleaning has improved since the early 1990s, modern wet cleaning compositions, methods and devices still cause damage to textiles in form of dimensional changes and color loss, especially after prolonged use. In traditional water-based washing, dimensional changes (shrinkage) and color loss are the result of water penetrating into the cavities of the textile fibers. During the drying process in a tumbler the evaporation of water creates pressure in the fiber cavities, thus resulting in damages to the fibers. In order to avoid or reduce dimensional changes, drying in a tumble dryer is avoided, sensitive garments are hanged to dry and cleaning is typically done at low water temperature and with little mechanical action (to avoid friction) while emphasizing the application of chemical compositions. Mechanical action in existing wet-cleaning systems is typically reduced by minimizing the time of drum rotation (i.e. the drum remains idle much of the time during the washing and conditioning cycles). As a result, the cleaning results in existing wet cleaning systems are generally poor.

Known devices and methods are not able to handle delicate textiles or only to a limited extend. Very sensitive items such as woolen jackets, silk ties, tight woven cashmere sweaters or high quality suits cannot be effectively wet-cleaned and subsequently tumbler dried in existing wet cleaning systems. A prolonged use of traditional wet cleaning methods will lead to dimensional changes/shrinkage, surface damages and dye or colour loss.

The known devices do not allow for the subsequent drying of the garments after the washing cycle. Typically, garments washed in existing wet cleaning systems need to be hanged to dry or dried in special drying cabinets, increasing the time and space requirement for processing the garments.

The present invention addresses the inherent weaknesses of existing wet cleaning systems.

Document EP 0 548 035 discloses a method and a apparatus comprising a drum enclosed in a basket, fluid supply input and output, conduits for flow of liquids, at least one apparatus for stocking the chemical compositions, hydraulic circuits command valves; moreover an electrical circuit cooperates with a controller for launch, duration, kind of programs to be used: precleaning, cleaning, rinse, spin-drying and/or drying.

Such (known) apparatuses aim to reduce mechanical forces on the garments to be cleaned and/or to emphasize the application of chemical compositions. They are known to focus on the reduction of mechanical friction to garments and to emphasize the application of chemical composition. Mechanical friction in existing wet-cleaning systems is typically reduced by minimizing the time of drum rotation (i.e. the drum remains idle much of the time during the cleaning and conditioning cycles).

One knows the Chinese document CN101343828A that discloses a cleaning machine in which a mixture of detergent and water is sprayed and spread over garments in order to improve the penetrability of functional detergent. Steam in high temperature is necessary sprayed over the laundry; in that way the consumption of the cleaning water can be reduced simultaneously to a good quality of the cleaning itself.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a novel and inventive concept that overcomes the prior art problems and limitations. The present invention can advantageously be applied both in professional or household settings without any risks and/or disturbances.

These and other objects are achieved in an apparatus for cleaning delicate textiles, comprising a motorized and rotating drum housed in a fluid tight basket, at least a water inlet and a fluid outlet, at least a first container for a first chemical composition.

According to the invention, the first container is appropriate to contain a warm mixture of water and the said first chemical composition; the apparatus comprises at least a conduit cooperating with a circulating means for mixing and circulating the said hot mixture between said first container and said circulating means; the apparatus further comprises a means for injecting and/or spraying said warm mixture into said drum and over dry textiles, said circulating means having an inlet for said warm mixture and at least an outlet cooperating with at least a first end of a conduit opening at its second end into the drum.

By “delicate textiles” one means items such as woolen jackets, sport jackets, silk ties, tight woven cashmere sweaters or high-quality suits made of water-sensitive protein fibers such as wool, cashmere, silk or other garments made of animal hair, animal skin as well as garments made of rayon and mixed spun materials; of course this list is non exhaustive and more generally “delicate textiles” comprises all textiles items or equivalents that have a tendency to dimensional changes/shrinkage, surface damages and dye or color loss during one or more cleanings. In other words, in the meaning of the present invention the term “delicate textiles” refers to items which have a tendency to lose dye or color, to crease, to felt or shrink when cleaned or washed in water. In order to avoid damages many of the delicate textiles are conventionally dry cleaned.

In a very interesting way, the apparatus according to the invention can be implemented in a professional as well as in a household setting.

According to a first embodiment of the invention, the apparatus comprises a first means for circulating the warm mixture into the drum through the spraying means, and/or a second means for circulating the warm mixture into the drum through the injection means.

By warm mixture one means a mixture whose temperature ranges between 10° C. and 35° C.

As will be detailed later, the invention involves at least three embodiments i.e. one with two circulating means (pumps for example); and two others with a single circulating means (pump for example).

In a specific way, a first heating means is located inside said first container.

Without departing from the scope of the invention, a first heating means is located outside said first container.

Besides, the apparatus may further comprise a second container for a second chemical composition, said second container having an opening for the second chemical composition to flow out of said second container and into said fluid tight basket.

More precisely, the first container comprises an outlet for evacuating the mixture not flowing through the circulating means.

The invention further encompasses a method for cleaning delicate textiles comprising at least a first contact between textiles and a washing fluid, a rotating of wet textiles in a motorized rotating drum provided in a fluid tight basket, at least a first rinse by contacting said textiles with clean water, at least a first extraction of rinse water wherein prior to the first contact between the textiles and washing fluid, a warm mixture of water and a first chemical composition is provided in a first container, then it is sprayed over the dry textiles during drum rotation.

Preferably, the warm mixture comprises 1 to 20% of first chemical composition.

More precisely, the warm mixture projected over the dry textiles enables an efficient cleaning of the textiles. Typically, at least more than half of the soils/impurities are solids such as dust and metal particles etc. Most of these impurities will be removed “right away”, just like brushing them off, in the spraying method. The remainder of the soil/impurities represents polar (water soluble stains like sugars, starch, food etc) and non polar type of stains (oil soluble) will be removed later in the cleaning cycle. The key is to obtain a quick coating of the garment fibers, in the first few seconds following the injection of the warm mixture into the drum. The coating will protect the textile fibers in the subsequent cleaning cycle.

In a very interesting way, the method according to the invention can be implemented either in a professional and/or commercial environment, or in a household setting.

Preferably, the warm mixture has a temperature between 10° C. and 35° C.

Furthermore the washing fluid is continually recirculated around the textiles, before being extracted out of the drum. By recirculating said washing fluid, the need for mechanical action through drum rotation is reduced.

Such a recirculation will reduce the need for mechanical action during the cleaning or the later reconditioning steps, mainly because this enables the fluid to move around the textiles, avoiding them the mechanical action through drum rotation. The warm mixture and/or washing fluid moves around the textiles rather than the drum around the textiles. Thus the textile fibers are not damaged, they are preserved. The risk of dimensional changes to textiles or fibers is thus greatly reduced.

Besides at least one pump is used to circulate said warm mixture within said container before it is sprayed over said dry textiles.

Furthermore once the at least one fluid extraction is completed, a second chemical composition is injected over textiles present into the drum. Said second chemical composition is preferably a conditioner composition.

Preferably, after injection of the second chemical composition, a second fluid extraction is provided. The thus treated textiles can then be directly loaded into the drum. They have a low humidity ratio (less than 40%) and they are slightly creased. No additional step is required.

BRIEF DESCRIPTION OF THE FIGURES

The above-mentioned and other features of the present invention, and the manner of obtaining them will become more apparent, and it will be best understood, by reference to the following description, taken in conjunction with the accompanying drawings in which:

FIG. 1, shows a first schematic embodiment of the invention;

FIG. 2, shows a second schematic embodiment of the invention; and

FIG. 3, shows a third schematic embodiment of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

FIG. 1 is a schema illustrating an apparatus (also named cleaning apparatus hereafter) for cleaning delicate textiles; this drawing only shows means that are necessary for a good understanding of the invention. The apparatus, in a known and essential way, comprises: a motorized drum 1 rotating about an horizontal axis; said drum is housed in a fluid tight basket 2. The apparatus is provided with some supply inlets and outlets such as a water supply inlet 20 and a drain outlet 11. It is also known to provide such a cleaning apparatus with at least a container for a chemical composition adapted to treat the laundry loaded into the drum. Typically, this or these containers are connected to the basket 2 through at least a conduit.

The currently used compositions are detergents, soap, pre-conditioner, conditioner as disclosed for example in WO 2010/097651. These compositions are generally mixed with water in specific container or container compartments; water flows over said compartment containing chemical composition(s). The mixture flows towards basket 2. Therefore said mixture of water and chemical composition(s) is introduced directly into the drum where they are heated if necessary.

A hydraulic circuit comprising at least a pump is provided to circulate the washing fluids; and programmed valves actuate this circulation. A program control device is also provided and designed to permit various cleaning cycles.

A heating means is provided in the basket 2 in order to heat the washing fluid. According to the invention the heating means 4 cooperates with a specific (first) container 5 that is, according to a preferred embodiment of the invention, directly linked to the basket 2, just underneath.

FIG. 1 relates to an embodiment where a single circulating means like a pump 61 is provided. A first conduit 53 is linked to a first opening of the specific container 5 and to said pump 61; said first conduit 53 allows fluid present in container 5 to flow out. A second conduit 54 is a supply conduit from pump 61 to container 5. Thus, fluid such as a warm mixture of soap and water is circulated and recirculated between pump 61 and first container 5. This fluid is also named “cleaning liquid” or “washing fluid” in the present specification.

Without departing from the scope of the invention pre-heated water can be used to heat the mixture. The pre-heated mixture can be introduced from outside said apparatus. In such an embodiment warm water for example can be injected directly into container 5.

Advantageously pump 61 has an opening cooperating with a conduit 71 ending by its second end into the drum 1. More precisely an injection means 7 is provided to inject the mixture, under pressure, into drum 1. The injection means 7, or sprayer, is positioned at the second end of the conduit 71. The man skilled in the art will determine the appropriate diameters and pressure allowing a spraying of the hot mixture into the drum 1. As an example the pressure is less than 5 bars.

The drum 1 is only partially filled through sprayer 7 as will be described later. Preferably the drum is half filled with said warm mixture during the cleaning cycle.

According to a preferred embodiment of the invention, the first container 5 is positioned underneath and tightly connected to the basket 2.

Moreover at least one valve 10 cooperates with a drain 11 in order to control the final extraction of the fluid out of the apparatus. Valve 10 can be connected to an outlet of the first container 5.

Of course a pre-programmed controller, not shown, is provided in order to control the flows, time, durations, temperatures of the cleaning cycle, in order to offer users with various cleaning programs; pre-cleaning, cleaning, rinse.

FIG. 2 shows a second embodiment of the invention that differs from the first embodiment by the injection means. According to this embodiment the sprayer 7 is replaced by a plurality of injectors 8,9 that inject the warm mixture directly into the drum 1. Besides, water (cold or warm) can be injected into the drum 1 through a plurality of water injection holes 20, distributed at some specific points around the drum 1. Preferably the water injection holes 20 are disposed in the upper part of the drum. Water flows more or less according to arrows F, to the connection 50 between drum 1 and first container 5, and then into container 5 where it is mixed with the first chemical composition basically contained in said first container 5.

As explained in relation with the first embodiment of the invention, said warm mixture is fully mixed thanks to pump 62 and connections 51, 52 between said pump 62 and the first container 5.

The second embodiment of the invention will preferably be used to introduce the warm mixture into the drum 1 at low pressure. This allows much higher loading ratio in the drum since the mixture enters the drum 1 from its top.

FIG. 3 illustrates a kind of combination of first and second embodiments. It relates to an apparatus comprising two pumps 61, 62; a first pump 61 is dedicated to the spraying means 7, the second pump 62 is dedicated to the injections means 8, 9. Both pumps 61, 62 are connected to the first container 5, to circulate the warm mixture.

As shown in FIG. 3 a second container 3 can be provided for another fluid such as a conditioner composition. Water is preferably introduced through the second container 3 which, however, is not compulsory.

The injections of the different compositions or mixtures are made successively.

A method for cleaning delicate textiles will now be described, susceptible to be implemented in apparatuses as described above.

Once textiles are loaded into the drum 1, the user selects a specific program which determine specific key parameters such as: short cycle, long cycle, maximum temperatures, rotation rpm, extraction rpm.

In any case launch of the cleaning apparatus starts injection of a small quantity of a first chemical composition into the specific (first) container 5. It has to be pointed out that this container 5 can be disposed either outside basket 2 or inside said basket. FIGS. 1, 2, 3 show a container 5 placed underneath basket 2.

The first chemical composition can advantageously be a soap composition as described in patent application WO 2010/097651. An amount of soap (for example) composition as well as water is injected into the container 5 with a proportion of composition to water of 1% to 20%.

Simultaneously, heating means 4 starts in order to heat said mixture of soap composition and water. The heating means 4 is disposed within or very close to container 5. Any kind of heating means can be provided: the man skilled in the art will choose depending on the whole context. The duration of said heating is set according to temperatures to be reached. For example the heating will be stopped when the temperature of the mixture inside container 5, is 25° C. or 30° C. The temperature can be between 10° C. to 35° C.

Alternatively, warm water within said range of temperatures could be used to eliminate the need for a heating means.

Then pump 61, 62 starts; or if several pumps, the pump 61 dedicated to the spraying starts. This will permit to inject said hot mixture into drum 1, through conduit 71.

At this step, the (highly concentrated) soap mixture is introduced into the drum 1 while the drum is rotating. Typically, at least more than half of the soils/impurities are solid such as dust and metal particles etc. Due to the injection under pressure of said hot mixture, most of these impurities will be removed “right away” (just like brushing them off) during this spraying method i.e. in the beginning of the washing process. The remainder of the soil/impurities represents polar (water soluble stains like sugars, starch, food etc) and non polar type of stains (oil soluble) will be removed later, during cleaning cycle.

The key is to obtain a quick coating of the garments fibers in the first few seconds following the introduction of the mixture into the drum 1. The mixture is introduced onto dry textiles which better absorb the mixture, in dry condition, than wet textiles would.

The coating will prevent water from penetrating deeply into the fibers cavities and thus from adhering to the fibers. As a result, water can be extracted more easily in the subsequent extraction steps.

As most of the soils/impurities can be removed in water-based cleaning, no or very little pre-spotting of the textile is needed with the present method; this is a substantial advantage over known methods. Actually pre-spotting is a manual action, borrow and thus costly.

Next step of the method comprises introduction of water into basket 2, by any means known per se. According to the first embodiment, water is introduced directly into the first container 5, for example through appropriate holes 20. According to FIGS. 2 and 3 water injection is provided through specific holes 20 disposed in the upper part of the drum 1.

The water injection duration as well as speed rotation of the drum 1 are determined by the man skilled in the art, in order to create a homogeneous coating of textiles with the warm mixture, more precisely with the first chemical composition. In order to obtain a homogenous coating of the garments, the drum 1 is rotated at a certain rotation speed for a certain length of time which will depend on the size of the drum; a larger drum will be rotated at lower rpm than a smaller drum. This contrasts with existing wet cleaning systems which try to minimize rotation speed and mechanical action.

Thanks to pumps 61, 62, the washing fluid is continually recirculated around the textiles in order to complete the cleaning cycle. The precise sequence of sub-steps in the cleaning cycle, its duration and mechanical action will depend on the type of garment wet-cleaned.

In other words in order to reduce the mechanical action during the cleaning or the conditioning cycles, the present invention will rotate (i.e. recirculate) the water and/or the water-composition mixture around the garments, using at least an integrated recirculation pump (i.e. water is extracted and reinjected into the drum). This will reduce the mechanical action (through drum rotation). According to the invention the textiles are rotated only periodically.

According to the invention the recirculation addresses the problem of stain removal in existing wet cleaning systems caused by mechanical action that inherently creates “friction” to the garments (which is necessary to remove stains).

In a next step a first extraction of the washing liquid can be done in order to eliminate the washing liquid and thus most of the suds which were removed from the textile fibers.

Then a second chemical composition such as a conditioner composition is injected into the drum 1 in order to “prepare” the textiles for drying and finishing (ironing). The conditioner composition does not need to be pre-heated. The conditioner composition will coat the garments with a protective thin layer of sizing.

In the drying method (if any), the conditioner composition will expand and remove almost entirely small creases. It has to be pointed out that conditioners used in existing wet cleaning systems do not have this capability. This is due to the combination and specific arrangement of the invention.

Thanks to the sizing, the garment surface will have been prepared for better gliding in the subsequent ironing and/or finishing. A slight ironing is thus necessary.

Next step consists of extracting water still adhering to the textiles. This extraction cycle uses varying drum rotation rates, depending of the type of the textiles to be cleaned. For example a low g-force of about 60 g will be used for sensitive silk garments, and a very high g-force will be used for some wool garments. By way of the force of extraction as well as the protective capabilities of the chemical composition, the present invention enables the removal of much of the moisture from the textiles, thereby reducing the subsequent drying time. 

1. An apparatus for cleaning delicate textiles, comprising a motorized and rotating drum housed in a fluid tight basket, at least a water inlet and a fluid outlet, at least a first container for a first chemical composition wherein the first container is appropriate to contain a warm mixture of water and the said first chemical composition, the apparatus comprises at least a conduit cooperating with a circulating means for mixing and circulating the said mixture between said first container and said circulating means, a means for injecting and/or spraying said warm mixture into said drum and over dry textiles, said circulating means having an inlet for said warm mixture and at least an outlet cooperating with at least a first end of a conduit opening at its second end into the drum.
 2. The apparatus according to claim 1, wherein it comprises a first means for circulating the warm mixture into the drum through the spraying means, and/or a second means for circulating the warm mixture into the drum through the injection means.
 3. The apparatus according to claim 1, wherein it comprises a heating means located inside said first container.
 4. The apparatus according to claim 1, wherein it comprises a heating means located outside said first container.
 5. The apparatus according to claim 1, wherein it further comprises a second container for a second chemical composition, said second container having an opening for the second chemical composition to flow out of said second container and into said fluid tight basket.
 6. The apparatus according to claim 1, wherein the first container comprises an outlet for evacuating the mixture not flowing through the circulating means.
 7. A method for cleaning delicate textiles comprising: contacting the textiles with a washing fluid; rotating of wet textiles in a motorized rotating drum provided in a fluid tight basket; rinsing said textiles by contacting said textiles with clean water; extracting rinse water wherein, prior to contacting the textiles with the washing fluid, a warm mixture of water and a first chemical composition is provided in a first container; spraying the warm mixture over the dry textiles during drum rotation.
 8. The method according to claim 7, wherein the warm mixture has a temperature between 10° C. and 35° C.
 9. The method according to claim 7, wherein the washing fluid is continually re-circulated around the textiles, before being extracted out of the drum.
 10. The method according to claim 7, wherein at least a pump is used to circulate said warm mixture within said first container before it is sprayed over said dry textiles.
 11. The method according to claim 7, wherein, once the step of extracting rinse water is completed, a second chemical composition is injected over textiles present into the drum.
 12. The method according to claim 11, wherein, after injection of the second chemical composition, a second fluid extraction is provided.
 13. The apparatus according to claim 2, wherein it comprises a heating means located inside said first container.
 14. The apparatus according to claim 2, wherein it comprises a heating means located outside said first container.
 15. The method according to claim 8, wherein the washing fluid is continually re-circulated around the textiles, before being extracted out of the drum. 